This invention relates to a control mechanism and is particularly directed to an improved throttle control mechanism for remotely controlling the position of the throttle lever on an internal combustion engine.
It is common practice today to control the throttle lever of an internal combustion engine remotely. Generally, the remote controls include a selector handle positioned in proximity to the operator's station with linkage extending to the engine. The selector handle, being movable between limit positions corresponding to the shut-off and full-throttle positions of the throttle lever, is operably associated with a releasable lock for holding the handle in desired intermediate positions between its limit positions. The throttle lever is usually biased toward its shut-off position by some means such as a governor spring.
A typical example of such a throttle control mechanism is one having a selector handle rotatably mounted on the frame of a vehicle with a cable connected to the throttle lever. Associated with the handle is an adjustable friction lock having a friction disc or discs which are resiliently urged against the selector handle to offset the governor spring force and thereby retain the selector handle in the desired position. Such control mechanism works satisfactory but has certain shortcomings. The larger the governor spring force, the larger the offsetting frictional force (disc pressure) needed for retaining the handle in a desired position, and thus the operator must exert a greater force to move the selector handle. The high friction disc pressure required heretofore results in frequent friction spring adjustment and excessive disc wear which is costly to repair.